The NIH Clinical Center Allergy and Immunology Clinical Fellowship Program recruits three to four highly qualified pediatricians and/or internists each year to train in allergy and immunology at the NIH Clinical Center. The fellowship is a three-year program, with the option of a fourth and fifth year of advanced research training for exceptional fellows. The first year of the program is designed to meet the majority of the clinical training requirements set forth by the Accreditation Council for Graduate Medical Education (ACGME) Residency Review Committee (RRC) for Allergy and Immunology. The A&I Clinical Fellowship Program focuses on clinical training in the setting of clinical research at the NIH Clinical Center, but also utilizes affiliated training sites to ensure a well-rounded clinical training experience. The second year is devoted to research, but also with clinical training focused on continuity of care for patients with primary immunodeficiency and allergic diseases. Subsequent years are devoted to advanced research training, including basic, translational, and clinical research. Fellows receive training in the fundamentals of clinical research and human subjects protection during their first month in the program, in preparation for their clinical rotations at the NIH. Throughout the first year of clinical training, all patients seen by fellows at the NIH Clinical Center are on research protocols. This allows immersion in clinical research with senior and junior NIAID investigators early in the program. Fellows are encouraged to identify potential areas of investigation during their clinical rotations. For their research projects, clinical fellows have a wide range of choices in clinical, translational and basic research from which to choose their research training experience. Most fellows work with investigators from the NIAID intramural research program, although occasionally, fellows may perform research in other Institutes. Career development is a central component of clinical fellow training at the NIAID. Fellows have the opportunity to participate in formal research training at many levels. The NIAID extramural Division of Allergy, Immunology, and Transplantation provides a formal lecture series reviewing the development of clinical protocols and grant writing as part of the didactic curriculum. Formal coursework in clinical research is provided by the NIH Clinical Center, including a formal certificate program in clinical research and a Masters Degree in Clinical Research provided jointly by the NIH Clinical Center and Duke University. Graduate level courses are also available through the Foundation for the Advancement of Education in Science. Fellows are mentored over time to transition to careers within the NIH, at extramural academic centers, government regulatory agencies, or pharmaceutical companies. Selection of fellows is based on a review of academic and clinical accomplishments and promise for a career as an independent investigator and leader in the specialty. A selection committee of nine faculty members review applications and interview candidates to identify promising candidates for training at the NIH. Clinical fellows are integrated into the clinical research mission of the NIAID and are active and productive contributors to the intramural research program. Graduates of the program have had productive careers as investigators and leaders in allergy and immunology at the NIH, extramural academic centers, federal, regulatory agencies and with pharmaceutical companies.